Module parsa::combinators

Parsers that combine/manipulate other parsers in some way.

All of the types here have corresponding methods in Parser for builder pattern-style construction.

Error coercion rules

When dealing with multiple parsers with different error types, they must have a conversion to a single type. This is usually determined by the first error type introduced, called the “target” type. The Parser::convert_err method can be used to set this target type explicitly.

For example with Chain, P2::Err must implement Into<P1::Err>. This is usually achieved with a higher ranked error type that fits the context of its usage.

#[derive(Debug, Error)]
pub enum MyErr {
    Unique,
    Empty(#[from] WordErr), // <- WordErr will implicitly be elevated to this type
}

Structs

• Chain
  Chains two parsers together.
• Many
  Repeatedly applies a parser, until it fails.
• Many1
  Repeatedly applies a parser, until it fails. Unlike Many, this parser errors if the first run errors.
• Or
  Attempts a second parser.